Pinking device



F. H. OGDEN PINKING DEVICE Oct. 11, 1938.

Filed Sept. 18, 1934 2 Sheets-Sheet F. H. OGDEN Get. 11, 1938.

PINKING DEVICE Filed Sept. 18, 1954 2 Sheets-Sheet 2 //V VEN OR:

Patented Oct. 1 1, 1938 UNITED STATES PATENT OFFICE I PINKING DEVICE Floyd H. Ogden, Watertown, Mala, assignor, by

mesne assignments, to Willcox & Gibbs Sewin; Machine Company, a corporation of New York ' Application September 18, 1934, Serial No. 744,542

15 Claims.

This invention relates in general to machines for simultaneously stitching a seam and pinking the stitched material along the seam. More particularly the invention relates to improvements in 5 the mounting and operation of the pinking device.

One object of the invention is to provide a pinking device that will insure a continuous severance of the material to produce a clean pinked edge regardless of any inaccuracies in the pinking cutter. A feature of the invention for attaining this object comprises an improved cutting bed for the plnking cutter adapted to tiltor rock in the direction required to cause each blade of the pinking cutter, however it may be misshapen or worn,

to fully contact the bed and cleanly sever the material. A pivot bed of this nature for the pinking cutter gives the advantage, over the rigid-bed heretofore in use, of operating under greatly reduced pressure.

Another object of the invention is to provide a pinking device that may be withdrawn from operation at the will of the operator while the sewing machine continues to operate but which, when 35 returned to its operating position, will again re- To the accomplishment of these objects andsuch others as may hereinafter appear, as will readily be understood by those skilled in the art,

the invention comprises the features and combinations of parts hereinafter described and then particularly pointed out in the appended claims. The nature and scope of the invention will be understood from a description of the preferred embodiment thereof illustrated in the accompanying drawings, in which:

Figure 1 is a. view, in front elevation, of so much of a sewing machine as is necessary to understand 0 the present invention together with the improved pinking device; 7

Fig. 2 is a detail, in front elevation and diagrammatic form, of the pinking cutter and its bed; I

85 Fig. 3 is a view, in perspective, of the pinking device as seen looking at the rear side of the front frame of the sewing machine;

Fig. 4 is a view. in vertical section, of the pinking cutter bed and its means of support, on the line 4-4 of Fig. 2; and

Fig. 5 is a view, similar to Fig. 4, illustrative of the accommodation of the pivot bed to a misshapen or worn cutter blade. In this view the position of the cutter bed is greatly exaggerated the true may not be more than a few thousandths of an inch but yet enough to prevent severance of the material when pressed on a fixed bed with since, in practice, the variation of the blade from the light pressure on the cutter which sumces for this invention.

In the drawings the improved pinking device has been shown, for purpose of illustration. as combined with the stitching mechanism of the well known Singer lock-stitch sewing machine,

but it willbe recognized by those skilled in the art 9 that the improved pinking device may be combined with any type of sewing machine for forming any kind of seam where pinking of the edge is desirable and the claims herewith are to be so construed.

In the illustrated embodiment of the invention the main frame It, see Figs. 1 and 3, of-the sewing machine is provided with a usual lower arm I, standard or trunk l and top arm 9 having-a usual head l2 (Fig. 1) within which are the needle bar H carrying the needle it of the stitch-forming mechanism and the presser foot bar l8 carrying the floating presser foot It. The book and bobbin case' 20 of the stitch-forming mechanism is g mounted on the hook shaft 2| beneath the sewing 86 machine bed 22. The four-motion feed foot, operating in a slot in the bed 22 by the feed rock shaft 24 and the feed lift shaft 26, 15 shown at 28 beneath the presser foot. All of the sewing machine mechanisms may be, and preferably are, the

same and operated the same as in the particular type of sewing machine with which the improved pinking device is combined.

A rotary pinking cutter 30 is rotatably supported at the lower end of a rocker frame 32 piv- 46 oted on a stud 34 carried by and projecting rearwardly from a bracket 36 secured to the head 12 by a screw through an ear 31 which sets against a shoulder on said head for holding the bracket rigid. A leaf spring 38 is secured to the upper end of the rocker frame and extends upward beyond an extension 39 of the bracket which latter supports a cam 40 secured to the rear end of a pin {I rotatable in the extension by means of a 7 hand lever 42 secured to its forward end. The 8 6 cam 4!! lies between and is engaged by the leaf spring 36 and a weaker follower spring 44. Both of these springs may be secured to the rocker frame 32 by a single screw 45 (Fig. 1) through With the hand lever 42 in a position depending from its pin 4| the cam riser has engaged the leaf spring 66 and has turned the rocker frame 32 clockwise, lowering the'pinking cutter 30 to engagement with its roller bed 46 as shown in Fig. 2. At this time the pinking cutter is held yieldingly to its roller bed by reason of the spring 38 being then under tension. An increase in the degree of pressure is attained by setting down the screw 46 (Figs. 1 and 3) thus turning down the rocker frame on its pivot or, conversely, increasing the tension of the spring 38.

The pinking cutter 30 should be rotated stepby-step, the advance at each step being equal to the advance of the material by the sewing machine feed mechanism whatever that may be. Accordingly the rotation of the pinking cutter is controlled by a ball clutch 50 (Fig. 3) of the well known over-running type mounted on the rocker frame stud 34. Beside the clutch, and connected to the outer ring which forms the driven member, is a gear 52 rotatable on the stud 34. The inner end of the pinking cutter shaft 3| has a gear 54 pinned thereto. The gears 52 and 54 intermesh with an idler gear 56 between them. Thus the gear 52 turns on the rocker frame pivot and the gears 54 and 56 move with the rocker frame 32 when it is raised or lowered. The pinking cutter driving train and its rocker frame thus move as a single unit and are never disconnected whether or not the pinking cutter is in operating position.

Power to actuate the clutch to turn the gear 52 intermittently and hence rotate the pinking cutter step-by-step is derived from an eccentric 60 shown for convenience of illustration as mounted on the sewing machine main shaft 62 but it is within the scope of the invention to mount the clutch eccentric on any other driving shaft. A rod 63 depends from the eccentric strap 64 having its lower end secured adjustably in a slot 65, formed in an ear on a face plate 66 attached to the inner rotor or driving. member of the clutch, by a wing nut clamp 61. The feed of the material being from right to left in Fig. 1, the clutch rotor is so set that the rotation of the clutch rotor, at each downward movement of the rod 63, causes the spring pressed balls between the rotor and the outer driven ring to grip thus rotating the gear 52 slightly contra-clockwise (viewing Fig. 1) and consequently rotating the pinking cutter in the direction of the sewing machine feed through an equal distance. Whenever the sewing machine feed step is changed, a commensurate change in the feed step of the pinl ing cutter is effected by adjustment of the eccentric bar along the clutch slot unless the clutch is operated intermittently from the variable throw sewing machine feed rock shaft. The usual brake to take back lash out of the clutch and insure a positive feed step is indicated by 68.

The blades of the pinking cutter at times become misshapen, due to wear and other causes, so that the combined cutting edges do not form 9.

true cylinder. Whenever a cutting blade does not lie wholly in a plane parallel to the axis of the shaft 3| it will not completely engage the surface of the pinking cutter bed 46 and, if the bed is fixed, this condition would result in a failure to sever the material unless excessive pressure is applied. Excessive pressure is not desirable because it may shorten the life of .the operating instrumentalities and increases the difficulty of obtaining a feed synchronous with that of the sewing machine feed mechanism. It will be observed that the pressure exerted by the spring 38 is relatively light and in order to maintain a continuous severance by the pinking cutter, even though some of its blades may be misshapen, a

pivot bed is employed adapted to rock or tilt to even the pressure as such diagonally engaging blades apply an initial excess of pressure at one or the other edge of the bed.

Accordingly the preferred pivot bed may conveniently consist of a cylindrical roller which, in the event the pinking device is combined with a lock-stitch sewing machine, may have the form of a flanged disk 46 as shown to accommodate the hook and bobbin case. The bed is supported on two pairs of guide rollers 10 which preferably have ball bearings (Fig. 1) to provide the least resistance under pressure. Each pair of rollers 10 has moderate side flanges to hold the roller bed thereon while rotating. Each pair of rollers 10 rotates freely on a pin 1| set into a depending portion of the sewing machine frame. The surface of the roller bed preferably is substantially flush with the surface of the sewing machine bed 22 (see Fig. 4).

Fig. 5 is illustrative of the accommodating action of the floating pinking cutter roller bed when a blade has become worn down at its rear end so that the cutter surface, at this point, is oblique to the surface of the roller bed in its normal position. The initial yielding pressure on the bed of the forward edge of the pinking cutter blade will cause the entire bed to tilt forward until the misshapen blade contacts the bed throughout its length, all substantially instantaneously because the angle to be closed is extremely slight, and all while the cutter and bed continue to rotate. During this period of correction the roller bed 46 may be supported by the forward roller of each pair 10. Should a pinking cutter blade be lower at its forward end than at its rear end then a reverse tilting of the roller bed to that just described will take place. Thus the rocking of the roller bed back and forth as may be required, as the diagonal blades of the pinking cutter successively contact with it,-insures a clean severance of the material regardless of misshapen blades and all under a relatively light pressure.

The roller bed mounting provides a substantially floating roller for receiving and correcting the uneven pressure of successive pinking cutter blades and may, from its action, be termed a pivot roller bed. It will be recognized that this feature of the invention is useful in any pinking device and whether or not the material is advanced by the pinking cutter or by other means.

While the particulars of construction herein set forth are well suited to one form of the invention, it is not to be understood that these particulars are essential since they may be variously modifled within the skill of the artisan without departing from the true scope of the actual invention as defined by the following claims.

through said rocker frame for yieldingly holding the cutter to its bed, a driving train carried by the rocker frame for rotating said cutter, means on said stud for actuating said driving train, and means for operating said actuator under control of the sewing machine. a

2. A sewing machine according to claim 1 in which means is provided for lifting the rocker frame relative to said cutter actuating means without disconnect ng the driving train, to remove the cutter from operating position while still continuing to rotate.

3. In a sewing machine the combination of a stitch forming mechanism; a mainframe; a lower arm; a rocker frame pivotally associated with said main frame and entirely clear of the lower arm; a rotary cutter carried by said rocker frame; a driving-mechanism; a bed for cooperation with said cutter; means for yieldingly holding the cutter to its bed; and means entirely clear of the lower arm nd cutter bed for mov ng said rocker frame and cutter to raised inoperative and lowered operative positions.

4. In a sewing machine the combination of a stitch forming mechanism; a main frame; a lower arm; a rocker frame pivotally associated with said main frame and entirely clear of the lower arm; a rotary cutter carried by said rocker frame; a driving mechanism; a bed for cooperation with said cutter; means for yieldingly holding the cutter to its bed; means entirely clear of the lower arm and cutter bed for moving said rocker frame and cutter to raised inoperative and lowered operative positions and for ma ntaining the cutter in the raised inoperative position; and means for continuously operating sa d cutter in both operative and inoperative positions.

5. In a sewing machine the combination of a stitch forming mechanism; a main frame; a rocker frame pivotally associated with said main frame; a rotary cutter on said rocker frame; a driving mechanism; a bed for cooperation with said cutter; spring means connected to said rocker frame for urging said cutter toward said bed; and means cooperable with said spring means for moving said cutter to lowered operative and raised inoperative positions relative to said bed.

6. In a sewing machine the combination of a stitch forming mechanism; a main frame; a rocker frame pivotally associated with said main frame; a rotary cutter carried by said rockerframe; a driving mechanism; a bed for cooperation with said rotary cutter; a pair of spring members'connected to said rocker frame; and means cooperable with said pair of spring members for moving said rocker frame to raiseand lower said cutter relative to said cutter bed.

8. In a sewing machine the combination of a stitch forming mechanism; a main frame; a rocker frame; a pivot for associating said rocker frame with said main frame; a rotary cutter carried by said rocker frame; a driving mechanism; -a bed for cooperation with said cutter; a cam; a spring member connected to said rocker frame and extending therefrom at one side of said cam, cooperable with the latter to urge the cutter toward said bed; a second spring member connected to said rocker frame and extending therefrom at the other side of said cam to maintain said first spring member in association therewith; and means for turning said cam to move said cutter upwardly and downwardly relative to said bed.

9. In asewing machine the combination of a stitch forming mechanism; a main frame; a lower arm; a driving shaft; a pivot; a rocker frame on said pivot; a rotary cutter canied by and movable with said rocker frame; a driving mechanism, between said driving-shaft and cutter, including a driving train for said cutter carried by said rocker frame; a bed for said cutter;

means spaced from said lower arm for moving said cutter to a lowered operative and to a raised inoperative position relative to said cutter bed and lower arm and for maintaining the cutter in the raised-inoperative position; and means for continuously connecting said driving shaft to said driving train whether the cutter be in an operative or inoperative position.

10. In a sewing machine the combination of a stitch forming mechanism; a main frame; a. lower arm; a driving shaft; a pivot; a rocker frame on said pivot; a rotary cutter carried by and movable with said rocker frame; a driving mechanism between said driving shaft and cutter, including a driving train for said cutter carried by said rocker frame; a bed for said cutter; means spaced from said lower arm for yleldingly maintaining said cutter in a lowered and operative position relative to said cutter bed and for moving the same'to a raised and inoperative position relative thereto; and means for continuously connecting said driving shaft to said driving train whether the cutter be in an operative or inopr erative position.

11. In a sewing machine the combination of a stitch forming mechanism; a driving shaft; a

pivot; a rocker frame on said pivot; a rotary cutter carried by and movable with said rocker frame; a bed for said cutter; a driving train for said cutter carried by said rocker frame; a pair of spring members connected to and extending upwardly from said rocker frame; and a cam cooperable with said members for moving said cutter from a lowered and operative position relative to said bed to a raised and inoperative position,

12. In a sewing machine the combination of a stitch forming mechanism; a driving shaft; a main frame; a rocker frame pivotally associated with said main frame; a rotary cutter carried by said rocker frame; a bed for cooperation with said cutter; a clutch carried by said rocker frame and operatively connected to said cutter; yielding means connected to said rocker frame for urging the latter and the cutter toward said bed; means cooperable with said yielding means for to a raised and inoperative positionrelative to said bed; and means for connecting said clutch and said driving shaft for continuously imparting a step by step movement to said cutter in both operative and inoperative positions.

13. Ina sewing machine the combination of a stitch forming mechanism; 'a main frame; a lower arm; a rocker frame pivotally associated with said. main frame and entirely clear of the lower arm; a'rotary cutter on the rocker frame; a main driving mechanism; a clutch; a chain of gears on said rocker frame between said clutch'and rotary cutter; and means forfmoving'said rocker frame to operative and inoperative positions relative to said lower arm.-

' 14. In a sewing machine the combination of a stitch forming mechanism; a driving shaft; .a

main frame; a -rocker'frame pivotaliy associated with said main frame; a rotary cutter carried by said rocker frame; a bed for cooperation with said cutter; a clutch-carried by said rocker frame I a sm moving said cutter from a lowered and operative and ope'ratively means connected to said rocker frame for urging the latter and the cutter toward said bed; and

means cooperable with said yielding meansvfor moving said cutter from a lowered andwperative to a raised and inoperative position relative to 'said'bed.

between said driving shaft and said cutten-a cam spaced upwardly from said'cutter bed, for

swinging said rocker frame relative tosaid cutter bed; means on said rocker frame cooperable with said cam; and-means for turning said cam to swing said rocker frame and cutter into operative and inoperative positions relative to said cutter Y v FLOYD H. OGDER.

connected to said cutter; yielding 

